1. Field of the Invention
The present invention relates to a spindle motor and more specifically to a spindle motor included in a disk drive apparatus.
2. Description of the Related Art
A spindle motor arranged to rotate a disk is installed in a disk drive apparatus. A known spindle motor and a known disk drive apparatus are described, for example, in JP-A 2001-35129. In the disk drive apparatus described in JP-A 2001-35129, a disk is adhered to a spacer whose inner circumferential portion includes a screw groove defined therein, and this spacer is screwed to an outer circumferential portion of a hub, the outer circumferential portion including a screw groove defined therein, whereby the disk is fixed to the hub (see paragraph [0014] of JP-A 2001-35129).
In the case where a fixing member including a screw groove defined therein is screwed to a hub including a screw groove defined therein as in the disk drive apparatus described in JP-A 2001-35129, the fixing member is mounted on the hub, and is then screwed to the hub by rotating the fixing member. At this time, if the fixing member is not stably mounted on the hub, the fixing member may be screwed to an outer circumferential portion of the hub in a tilted condition. This may result in a failure to securely fix a disk to the hub. There is accordingly a demand for the fixing member to be stably mounted on the hub.